Prefabricated and portable utility pens for enclosing pets have long been available in the market place. Despite allegations of portability, most prior art fences are complex in structure, requiring considerable time for erection and special equipment to handle and move them. Moreover, few can be packaged compactly in containers for ordinary handling and placing on shelving of retail stores for display purposes and ready access to the public. Effective vertical stacking of the containers in storage or on display shelves requires the use of structural strong container materials with sufficient strength to withstand the considerable pressure exerted against the bottom most containers. Otherwise considerable damage can occur to the containers. The cost of container materials to withstand treatment are substantial higher than the normal corrugated paper containers.
Finally, tensioning of the fence material has to date required complex and heavy mechanisms that limit the portability of the packaged fence components. This also complicates and lengthens erection time.
Some attempts have been made to provide light weight portable fencing by fabricating the fence rails and the gate assembly of telescoping hollow metal tubes and woven fence fabric. The structure provided by the telescoping tubes is indeed light weight but has limited utility since the integrity is not sound. This may cause significant problems when large animals are to be enclosed.
An early example of a portable pen is described in U.S. Pat. No. 3,072,385 issued on Jan. 8, 1963 to Johnson. Four end posts connected by top and bottom horizontal struts are circumscribed by flexible fencing material fabric. Tensioning of the fabric is provided by a capstan located at one of the end posts. A preassembled gate structure is also provided.
Another fence structure of interest is discussed in U.S. Pat. No. 4,422,622 issued on Dec. 27, 1983 to Broski. The Broski patent illustrates the use of individual fence panels made with hollow telescopically fitting tubes for the uprights and upper and lower rails. Each panel is a separately assembled structure having separate fencing fabric tensioned for each panel. The individual panels are then secured to each other and to a preassembled gate assembly to form the enclosure.
None of the prior art portable fences provide any solution to the problem of packaging the fences for compact storage and display. Portability is largely a matter of opinion as the combination of fence components and the container produce a heavy often bulky package, making storage and display of more than one container problematical.
Thus, a paramount object of the present invention is to provide a light weight portable fence with components that can be arranged within the container to provide the container with internal structure sufficient to withstand considerable outside pressure thereby allowing the container to be composed of ordinary packaging materials.
A further object of the present invention is to provide a fence of made of light weight components but with significant assembled integrity to withstand considerable interior force.
Another object of the present invention is to provide a utility fence portable in nature, easily assembled and disassembled, which has internal structural integrity thereby minimizing damage to the container due to vertical stacking of the containers for storage and display purposes.
A still another object of the present invention is to provide a utility pen that has a simple structure for tensioning the fencing fabric circumscribing essentially the entire perimeter of the rail structure of the utility pen.
Yet another object of the present invention is to provide a utility pen that has a frame member including a swingable gate mounted within the frame member for positioning within the utility pen.